Author: Xu FC

Console配置

• 查看是否支持串口，出现以上console enabled表示支持

 -bash-4.2# dmesg | grep tty
 [ 0.000000] Command line: BOOT_IMAGE=/vmlinuz-3.10.0-862.11.6.el7.x86_64 root=/dev/mapper/centos-root ro [rd.lvm.lv](http://rd.lvm.lv/)=centos/swap vconsole.font=latarcyrheb-sun16 [rd.lvm.lv](http://rd.lvm.lv/)=centos/root crashkernel=auto vconsole.keymap=us rhgb quiet console=tty0 console=ttyS0, 9600 LANG=en_US.UTF-8
 [ 0.000000] Kernel command line: BOOT_IMAGE=/vmlinuz-3.10.0-862.11.6.el7.x86_64 root=/dev/mapper/centos-root ro [rd.lvm.lv](http://rd.lvm.lv/)=centos/swap vconsole.font=latarcyrheb-sun16 [rd.lvm.lv](http://rd.lvm.lv/)=centos/root crashkernel=auto vconsole.keymap=us rhgb quiet console=tty0 console=ttyS0, 9600 LANG=en_US.UTF-8
 [ 0.000000] console [tty0] enabled
 [ 0.000000] console [ttyS0] enabled
 [ 0.961352] 00:03: ttyS0 at I/O 0x3f8 (irq = 4) is a 16550A
 [ 0.981919] 00:04: ttyS1 at I/O 0x2f8 (irq = 3) is a 16550A

• 修改配置文件/etc/default/grub， 设置波特率9600，tty0/ttyS0根据第一步命令查出

 -bash-4.2# vi /etc/default/grub 
 
 GRUB_TIMEOUT=5
 GRUB_DISTRIBUTOR="$(sed 's, release .*$,,g' /etc/system-release)"
 GRUB_DEFAULT=saved
 GRUB_DISABLE_SUBMENU=true
 GRUB_TERMINAL_OUTPUT="console"
 GRUB_CMDLINE_LINUX="[rd.lvm.lv](http://rd.lvm.lv/)=centos/swap vconsole.font=latarcyrheb-sun16 [rd.lvm.lv](http://rd.lvm.lv/)=centos/root crashkernel=auto vconsole.keymap=us rhgb quiet"
 GRUB_DISABLE_RECOVERY="true"
 GRUB_CMDLINE_LINUX_DEFAULT="console=tty0 console=ttyS0, 9600"

• 更新grub2配置文件

 -bash-4.2# grub2-mkconfig -o /boot/grub2/grub.cfg
 Generating grub configuration file ...
 Found linux image: /boot/vmlinuz-4.18.8-1.el7.elrepo.x86_64
 Found initrd image: /boot/initramfs-4.18.8-1.el7.elrepo.x86_64.img
 Found linux image: /boot/vmlinuz-3.10.0-862.11.6.el7.x86_64
 Found initrd image: /boot/initramfs-3.10.0-862.11.6.el7.x86_64.img
 Found linux image: /boot/vmlinuz-3.10.0-123.el7.x86_64
 Found initrd image: /boot/initramfs-3.10.0-123.el7.x86_64.img
 Found linux image: /boot/vmlinuz-0-rescue-8448916f01fd410d9ad2ffb2f7c3ddee
 Found initrd image: /boot/initramfs-0-rescue-8448916f01fd410d9ad2ffb2f7c3ddee.img
 done

• 重启